Abstract:This paper discusses for the first time the combined optoelectronic-electromagnetic modelling of a new technology that represents a paradigm shift in the way millimetre-wave and terahertz electronics can be implemented using the REconfigurable Terahertz INtegrated Architecture (RETINA) concept. Instead of having traditional metal-pipe rectangular waveguide structures with metal sidewalls, RETINA structures have photo-induced virtual sidewalls within a high resistivity silicon substrate. This new class of substrate integrated waveguide (SIW) technology allows individual components to be made tuneable and subsystems to be reconfigurable, by changing light source patterns. Detailed optoelectronic modelling strategies for the generation of virtual sidewalls and their electromagnetic interactions are presented in detail for the first time. It is found with double-sided illuminated RETINA structures that an insertion loss of 1.3 dB/ λg at 300 GHz is predicted for the dominant TE10 mode and for a cavity resonator a Q-factor of 4 at 173 GHz is predicted for the TE101 mode. While predicted losses are currently greater than other non-tuneable/reconfigurable SIW technologies, there is a wide range of techniques that can improve their performance, while still allowing completely arbitrary topologies to be defined in the x-z plane. For this reason, it is believed that this technology could have a profound impact on the future of millimetre-wave and terahertz electronics. As a result, this paper could be of interest to research groups that have the specialised experimental resources to implement practical demonstrator exemplars.